The present invention relates to a device for exchanging heat comprising a plate stack (1) of at least a first, a second, and a third plate (4, 5, 6). The three or more plates are stacked one on top of the other and have recesses (7) which are arranged in a regular pattern on a plane of the respective plates (4 - 6). The first and the second plates (4, 5) as well as the second and the third plates (5, 6) are stacked in such a manner that each adjacent plate forms at least one common cooling channel (8), which is accessible to a fluid, running in a direction on the plane of plates, and formed by way of recesses (7), which partially but not entirely overlap, in the adjacent plates. The one or more cooling channels (8a) of the first and second plates (4, 5) are entirely spatially separated from at least one cooling channel (8b) of the second and third plates (5, 6). The invention also relates to a method for producing the plate stack.